Auditory prosthesis patients (e.g., cochlear implant patients) often have trouble understanding relatively quiet sounds, such as soft speech. Traditional auditory prosthesis systems attempt to overcome this limitation by amplifying audio signals presented to auditory prosthesis patients before the signals are otherwise processed. However, in order to prevent already loud sounds from being further amplified, many auditory prosthesis systems use adaptive gain control (“AGC”) to selectively amplify sounds below a predetermined input sound level (e.g., 60 dB SPL) and compress sounds above the predetermined input sound level.
Unfortunately, adaptive gain control also amplifies undesirable sounds, or noise, present below the predetermined input sound level. For example, environmental noise, system noise (e.g., microphone noise), and other types of noise are often present within the 20-40 dB SPL range, while soft speech is often within the 40-50 dB SPL range. In these situations, traditional adaptive gain control amplifies both the soft speech and the noise, thereby making it even more difficult, in some instances, for a patient to understand the soft speech.